By placing the child on the carrousel, handing it the electrically charged ball to hold (in a manner that would not harm the child of course) and placing the bar magnet at the middle of the carrousel, one would arrive at a situation that is similar to the toy model that was proposed in earlier lectures. One could then vary the angle of the bar magnet with respect to the plane of motion of the child to gauge the its effect on the measured hyperfine field or one could increase the speed of the carrousel (again in a safe manner for the child) to increase its angular momentum to see how this will effect the hyperfine field.